The overall objective of this project is to compare the bioavailability of Neosten with that of two generic fluoride preparations. It will test the hypothesis that Neosten is pharmacokinetically unique, and that it will confer a lower peak-basal variation and that it has a greater capacity to avert toxic fluoride threshold, than generic preparations. This goal will be pursued by a single dose bioavailability study of three drugs in 12 normal women.